The floor for the variable rate base of the debt instrument.

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- Definition

Liabilities Subject To Compromise, Accrued Interest

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No definition available.

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- Definition

Liabilities Subject To Compromise, Debt

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No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

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- Definition

Amount of debtor-in-possession borrowings outstanding.

+ References

No definition available.

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Debt - Debt Obligations (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Debt - Debt Obligations (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Jan. 31, 2018
Debt Instrument [Line Items]
Total debt		$ 4,595	$ 4,343
Unamortized discount and debt issue costs		0	(95)
Current portion of long-term debt		(1,815)	(58)
Amounts reclassified as liabilities subject to compromise		2,780	0
Total long-term debt		0	4,285
Debtor-in-possession financing		148	0
Write off of deferred debt issuance cost	$ 90
Senior Secured Term Loans due April 30, 2019
Debt Instrument [Line Items]
Total debt		$ 0	8
Effective interest rate		6.21%
Senior Secured Term Loans due April 30, 2019 \| LIBOR
Debt Instrument [Line Items]
Specified margin on reference rate		3.50%
Senior Secured Term Loans due April 30, 2019 \| LIBOR \| Minimum
Debt Instrument [Line Items]
Floor on variable rate		1.00%
Senior Secured Note due May 1, 2024
Debt Instrument [Line Items]
Interest Rate		9.375%
Total debt			1,092	$ 1,092
Senior Secured Notes due November 29, 2024
Debt Instrument [Line Items]
Interest Rate		8.00%
Total debt		$ 500	500
Senior Secured Notes due February 15, 2025
Debt Instrument [Line Items]
Interest Rate		8.00%
Total debt		$ 1,000	1,000
Senior Secured Notes due May 15, 2026
Debt Instrument [Line Items]
Interest Rate		7.75%
Total debt		$ 1,000	1,000
Senior Unsecured Notes due May 1, 2020
Debt Instrument [Line Items]
Interest Rate		9.375%
Total debt		$ 182	232
Senior Unsecured Notes due September 1, 2022
Debt Instrument [Line Items]
Interest Rate		7.75%
Total debt		$ 182	182
Senior Unsecured Notes due June 15, 2023
Debt Instrument [Line Items]
Interest Rate		6.375%
Total debt		$ 324	324
Senior Secured Notes
Debt Instrument [Line Items]
Amounts reclassified as liabilities subject to compromise		2,092
Senior Unsecured Notes
Debt Instrument [Line Items]
Amounts reclassified as liabilities subject to compromise		688
Senior Secured Term Loans and Senior Notes
Debt Instrument [Line Items]
Prepetition accrued interest on senior secured 1.5 lien and unsecured notes		117
Debtor-In-Possession Senior Secured Superpriority Revolving Credit Facility
Debt Instrument [Line Items]
Debtor-in-possession financing		$ 148	0
Reserve-Based Loan Facility, Due November 2021
Debt Instrument [Line Items]
Unused capacity, commitment fee percentage		0.375%
Line of Credit \| Reserve-Based Loan Facility, Due November 2021
Debt Instrument [Line Items]
Total debt		$ 315	$ 100
Line of Credit \| Reserve-Based Loan Facility, Due November 2021 \| LIBOR \| Minimum
Debt Instrument [Line Items]
Specified margin on reference rate		2.50%
Line of Credit \| Reserve-Based Loan Facility, Due November 2021 \| LIBOR \| Maximum
Debt Instrument [Line Items]
Specified margin on reference rate		3.50%